\begin{tikzpicture}
	\tkzDefPoints{0/0/A, 0.9/0/C, 3/0/B}
	\tkzDrawSegments[xianduan={below=0pt}](A,C  C,B)
	\tkzLabelPoints[above=0.3em](A,C,B)
\end{tikzpicture}

